Cruise control systems
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Transcript of Cruise control systems
CRUISE CONTROL SYSTEMS
CRUISE CONTROL SYSTEMS
By Yusha Patel (TYME-A)
Cruise control is a new technological development which incorporates a factor of comfort in driving.Safety is only a small benefit of this system. In short, cruise control can be said to be a system which uses the principles of radar to determine the distances between two consecutive moving vehicles in which either one or both of them is incorporated with this system.
Basic Information about Cruise Control Systems
CONTENTSINTRODUCTIONWHAT IS CRUISE CONTROL ?BASIC OPERATIONHOW TO SET CRUISE CONTROL?ADAPTIVE CRUISE CONTROLPARTS AND WORKINGDANGERS OF CRUISE CONTROLFUTURE ASPECTS CONCLUSION
INTRODUCTIONEvery minute, on average, at least one person dies in a crash. Air bags and seat belts save tens of thousands of people a year.But the ultimate solution and the only thing that will save far more lives, limbs and money is ? till 1958.Cruise control was commercially introduced in 1958 as an option on the Chrysler Imperial.
WHAT IS CRUISE CONTROL?
Cruise control is a system, which automatically controls the speed of an automobile.The system takes over the throttle of the car to maintain a steady speed as set by the driver.Most cruise control systems dont allow the use of cruise control below a certain speed.Blind inventor and mechanical engineer Ralph teetor invented cruise control in 1945.
BASIC OPERATIONThe basic operation of a cruise controller is to sense the speed of the vehicle, compare this speed to a desired reference, and then accelerate or decelerate the car as required.
A simple control algorithm for controlling the speed is to use a "proportional plus integral" feedback.
The performance of the system is robust with respect to its mass uncertainty.
Block diagram of cruise control model
HOW TO SET CRUISE CONTROL ?On &off
Brake & clutch
ADAPTIVE CRUISE CONTROLAdaptive Cruise Control (ACC) is an automotive feature that allows a vehicle's cruise control system to adapt the vehicle's speed to the traffic environment.In May 1998, Toyota became the first to introduce an ACC system on a production vehicle, luxury sedan.
ACC systems detect the vehicle ahead through the use of either radar or lidar (light detecting and ranging).
Lidar based ACC systems are limited due to their poor working in bad whether.
PARTS AND WORKINGThe main components of a typical radar-based ACC system are Fusion sensorHeadway control unitThrottleBrakeDashboard display
Fusion sensor: It is a combination of sensors and processors. They are
Millimeter-wave radarStereo cameraImage processorFusion processor
Architecture of a radar-based ACC system
Millimeter wave radar: It is a sensor which uses millimeter wave for detecting the position and velocity of a distant object.
Range is calculated using the formula C = 2*R/T Where C is the velocity of light R is the range T is the time of flight of transmission.
Stereo camera: The cameras function is detection of cars and other objects in the roadway. Image processor: It processes the images from the stereo camera and the data fed into the fusion processor.Fusion processor:The function of fusion processor is Data Fusion.
Headway control unit: It has control on the brakes and throttle and uses dashboard for immediate warnings.
Canceling Cruise Control Operation:Brake pedal is pressed'Off' button is pressedVehicle Speed < 25 mphAn ACC system fault is detected
A car model with advanced cruise control system
Its use on wet and slippery roads may cause serious problems.DANGERS OF CRUISE CONTROL
FUTURE ASPECTSCACC(co-operative adaptive cruise control) tested in California.
At 100 km/hr, that would amount to a distance between cars of less than 14 meters (roughly two car lengths).
Fujitsu Ten has demonstrated a prototype system for so called stop-and-go adaptive cruise control.
Fully autonomous car is probably not viable in the foreseen future.
Near by vehicles would be in constant communication with each other and act co-operatively.
It will probably take decades, but car accidents may eventually become almost as rare as plane crashes are now.